SOCS1 and plasma cell myeloma: Previous studies have also indicated that CpG island methylation in various carcinomas such as hepatocellular carcinoma, multiple myeloma, acute myeloid lymphoma, and colorectal cancer is responsible for silencing the SOCS-1 gene (Chen et al., 2003; Galm et al., 2003; Nagai et al., 2003; Tischoff et al., 2007; Kang et al., 2016).